Negative glow display



Feb. 15, 1938. A. F. HENNINGER, JR

NEGATIVE GLOW DI SPLAY Filed March 26. 19s? 25 readily, and valuableflaming effects over the I prefer however, to so form each letter ordesign 25 35 through a negative glow tube embodying the insisting of anelongated sheet 20 is connected to 35 Patented Feb. 15, 1938 j 9 vUNITED STATES PATENT OFFICE NEGATIVZfi DISPLAY a, I I Andrew F.Henninger, In, Chicago, Ill.

' Application March 26, 1937, Serial No. 133,198

In Canada April 11, 1936 '7 Claims. (Cl. 176-14) The present inventionrelates to negative glow at the end of the tube opposite the press I.The display devices and particularly to an' improved sheet 9 mayhave-its side edges Ii and i2 spaced method of. construction thereforhaving certain from the tube 5. It is held in position by a advantagesover that shown in my-Patent No. bracket i3 which is fixed-to the sheetii). The

5 2,069,308. l bracket I3 is an L-shaped metal strip. Holes are 5 In theabove application, I have disclosed a provided in thelsheets 9 and iii.A pair of small structure wherein the necessity for use of supmetalstrips I311 and I3b are welded to the strip port wires to brace theelectrodes is to a subiii in the holes and project over the adjacentstantial degree overcome. The structure as disportions of the sheets 9and iii. The mica sheet l closed in the previous application is one inwhich 9 maybe supported directly from the glass at 10 a ilatv or curvedsheet of mica or other suitable the end opposite the sheet ill or itmaybe supmaterial is made of such a size as to position the ported by meansof lead wires i4, i5 and I6 as electrodes supported thereby within .thetube shown in Figures 1 and 2. without further mounting means. Aplurality of electrodes 11, which are shown 5 The present inventionrelates toqcertain imin the form of letters, are formed from a metalprovements which have been found to be advansheet by stamping, etching,or sawing the design. tageous for some of the constructions of displayThe electrodes are mounted on the front side of devices. The presentinvention contemplates the the sheet 9 by means of extensions l8 at theprovision of a, plurality of sheets of mica supporttop and i9 at thebottom edges of the electrodes.

ing structure for negative glow electrodes in The extensions i8 and i9project beyond the -2 which the mica sheets directly supporting theedges of the sheet 9 and are bent over the edges electrodes may bespaced from the walls of the to thereby secure the metal electrodes tothe glass tubes. With the improved construction, sheet 9. Each of theletters l'l may be indeit is possible to connect the electrodes morependently connected to a conducting lead l6.

edges of the mica sheets may be obtained. that the extensions l3 and I 9may extend longi: I will describe a preferred form of the inventudinallyof the sheet 9, a distance suihcient to tion by reference to' theaccompanying drawing. overlap or connect to the longitudinalextension Itis to be understood, however, that the drawing I8 or iii of the nextadjacent letter or design to and description are illustrative only andare not thereby electrically connect all of the letters. In 30 to betaken as limiting the invention except in so order to securegoodelectrical contact, the entire far as it is limited by the claims.designmay be formed in one piece or the longi- In the drawing: I tudinalextensions l8 and IQ of. adjacent letters Figure 1 is a longitudinalsectional view may be welded together. A'back electrode convention. thelead I. A metal shield 2i is interposed be- Figure 2 is a plan sectiontaken on the line tween the mica sheet 9 and the electrode 20, and 2-2of Figure 1. this sheet is preferably insulated from the sheet Figure 3is a sectional view taken on the line electrode 20 by insulating washers22 which 3-3 of Figure '1. serve to space the shield 2i and theelectrode 20 40 Figure 4 is a sectional view similar to Figure 3 apart.Insulating washers 23 also space the of a slightly modified form of theinvention, and shield 2| from the mica sheet 9.

Figure 5 is a side view of an electrode used in In front of the micasheet 9 and spaced from the present construction. the letters I! is afront electrode 24 consisting Referring now in detail to the drawing theof an elongated metal strip. spaced from the 45 numeral 5 indicates theusual negative glow tube. mica sheet by suitable insulating washers 25.A base 6 is provided on the tube for making the The front electrode 24is connected to a lead I! necessary connections as will be readily underby which it may be connected to a source of curstood. The tube 5 has areentrant-stem' I in rent. If lead I! is disconnected from a sourcewhich suitable conductors 3 are secured. The of current, then electrodewill merely act as 50 tube 5 has a filling ,of a suitable gas asdescribed a silhouette or shield. in my prior application. The fact thatthe longitudinal edges'of the The tube ihas a supporting structuretherein plate'9 are spaced a distance from the inside composed of alongitudinally running sheet 9 of surface of the tube 5 provides arestricted pasmica d she t lo'flttmg snugly. in the tube 5 sage forelectrons flowing around the edges of 55 In the course of evacuatingfthe tube 5, it is heated by means of a bombarder in a, manner wellknown in this art. This heating may cause the metal electrodes to expandsubstantially and in order to prevent permanent warping of electrodesafter the heating has discontinued and the tube hascooled, the sheet Illshould be sufllciently thin to allow it to bend during the heatmgoperation in case the electrodes press against it. It has been foundthatif mica is used for the sheet III the thicknesspi' the mica sheet shouldpreferably be about .008 inchi It will be noted that the shield 2| isslightly larger than the electrode 20 so that as one is looking at the,envelope in the direction as it is shown in Figure 1, the electrode 20cannot be seen but the glowing effect is readily seen at the edges ofthe shield 2h The portions l8 and 59 which are bent over the edges ofthe sheet 9 are preferably covered with an insulating cement or varnish.

In the device shown in Figure 4 a double sided sign is produced. In thisform a metal backing which is bent in a step formation is used tosupport a plurality of mica sheets 9:: and 9b. The backing 26 need notbe of this particular formation but it provides an advantageousconstruction. The micasheets 9c and 9b and the sheet it may be desirablysecured to the backing 26 by metal tabs 2? which pass through holespunched in the mica sheets and are welded to the backing 26.Theelectrodes ll are rounded on the outside of the sheets to and 91).Also sheets 2d may be used in this form of the device as well asin theform shown inFigures 1, 2 and 3. Electrical connection is made to theelectrodes I! by a plurality of leads 28 and 29. The portions l8 and 19of the electrodes I! are preferably covered with insulating cement. Alsothe leads 28 and 29 as well as the leads I 4, l5 and I6 should becovered with insulating cement;

From the above description it is believed that the constructionandadvantages of this device will be readily apparent to those skilledin this art. Having thus described my invention what I claim as new anddesire to secure by- Letters Patent is:

1. In a negative glow device, an envelope, a plurality of electrodes insaid envelope, a dielectrlc sheet of substantial area within saidenvelope, said sheet having the electrodes mounted thereon whereby thesheet provides the principal support for said electrodes,- a presswithin said envelope, terminals extending from said press, means forelectrically joining the electrodes and the terminals. a supportingmember of insulating material within said envelope and engaging theinner wall thereof, said supporting member being arranged transverselyof the'dlelectric sheet, the dielectric sheet being supported by saidmember.

2. Ina negative glow device an elongated envelope, a plurality ofelectrodes in said envelope, a dielectric sheet of substantial areawithin said envelopeg said sheet having the electrodes mounted thereonwhereby the sheet provides the principal support for said electrodes, apress within said envelope, at the one end thereof terminals extendingfrom said press, means for electrically joining the electrodes and theterminals, a supporting member of insulating material within saidenvelope and engaging the inner wall thereof adjacent the end of saidenvelope remote from the press, said supporting member being arrangedtransversely of the dielectric sheet, the dielectric sheet beingsupported by said member.

3. In a negative glow device, an envelope, a

plurality of electrodes in said envelope, 8. dielec-v tric sheet ofsubstantial area. within said envelope, said sheet having the electrodesmounted thereon whereby the sheet provides the principal support forsaid electrodes, a press within said envelope, terminals extending fromsaid press, means for electrically joining the electrodes and theterminals, a thin dielectric disk in said envelope remote from saidpress and extending transversely of the dielectric sheet, said diskengaging the inner wall of the envelope and said dielectric sheet beingfixed to the disk and thereby held in position in said envelope.

i 4. In a negative glow device, an envelope, a plurality of electrodesin said envelope, at dielectric sheet of substantial area within saiden'- velope, said sheet having the electrodes mounted thereon wherebythe sheet provides the principal support for said electrodes, a presswithin said envelope, terminals extending from said press, means forelectrically joining the electrodes and the terminals, 8. thindielectric disk in said envelope remote from said press and extendingtransversely of the dielectric sheet, said disk engaging the inner wallof the envelope and said dielectric sheet being fixed to the disk andthereby held in position in said envelope, said insulating membercomprising a thin disk of mica.

5. In a negative glow display device an elongated envelope, a presswithin said envelope at one end thereof, a thinimica disk at the otherend thereof, the edge of the mica disk being engaged with the inner wallof the envelope an electrode assembly comprising a plurality of spacedelectrodes and supporting means therefor extending from said press tosaid disk and supported by the press and disk.

6. In a negative glow display, an elongated envelope, an electrodeassembly in said envelope, and means supporting said assembly in spacedrelation to the walls of the envelope, said supporting means including atransparent support at one end of the envelope through which the displayis visible.

7. In a negative glow device, an envelope, a plurality of electrodes insaid envelope, a pair of spaced dielectric sheets of substantial areawithin said envelope, part of said electrodes being mounted on one ofsaid sheets and part of said electrodes being mounted on the other sheetwhereby each sheet supports its electrode in spaced relation withrespect to the envelope, a spacing member secured to both of said sheetsand holding them in spaced relation, said electrodes having extensionsat their opposite edges which are bent over the sheets to thereby securethe electrodes to the sheets.

, ANDREW F. HENNINGER, JR.

